Field of the Invention
The present invention relates to a golf ball having a core and a cover of one layer or a plurality of layers. The invention relates more particularly to a golf ball which, by maintaining a good rebound and having a reduced spin rate, is able to achieve an increased distance.
Prior Art
It is known that the hardness and resilience of crosslinked rubber vary with the moisture content therein. In light of this, various ways of adjusting the moisture content within rubber compositions in the manufacture of golf balls have been proposed. For example, JP-A 10-85367 discloses a technique that holds down decreases in core resilience by minimizing the moisture present in rubber compositions for golf balls.
JP-A 2002-102388 describes an attempt in which, as one means of lowering the rebound of practice golf balls, powdered rubber that has been subjected to moisture absorption is added to a rubber composition. However, such prior art does not address the challenge of providing a golf ball for regulation play which, by maintaining a good rebound and having a reduced spin rate, is able to achieve an increased distance.
Also, JP-A 2003-126300 discloses art which increases the rebound of golf balls by using zinc oxide having a small particle size in a rubber composition for golf ball cores. However, because this art does not control the crosslink density of the core, a core material which undergoes no decrease in resilience over time and experiences little energy loss cannot be reliably obtained.
It is therefore an object of this invention to obtain a core material which undergoes little decrease in resilience over time and experiences little energy loss, and thus to provide a golf ball which has a reduced spin rate and undergoes little decrease over time in rebound.